About 4,260 of the 7,000 chemical barrels that were swept into a major river in northeast China's Jilin Province Wednesday had been recovered by noon Saturday, local authorities said.

But the unrecovered barrels are now flowing faster down the river because the Fengman Dam, located on the upper reaches of the Songhua River, opened its floodgates Friday afternoon to discharge flood waters.

Some 3,000 chemical-filled barrels and 4,000 empty barrels were swept into the Songhua River Wednesday morning after floods hit the warehouses of two chemical companies in Jilin City, Jilin Province. Each chemical-filled barrel contains 160 kilograms of chemicals.

The empty barrels have been easier for workers to retrieve, meaning the unretrieved barrels are more likely to be chemical-filled.

Although downstream dams have been helpful in intercepting the barrels, experts are concerned the chemical-filled barrels may explode if they slam into a dam at high speed.

The barrels will cross into Heilongjiang Province at 10 p.m. Saturday, Professor Liu Guoliang, a chemist leading Heilongjiang's retrieval team, estimates.

Jilin's Communist Party chief, Sun Zhengcai, and Governor, Wang Rulin, have ordered more vessels be mobilized to join in the retrieval effort.

Nearly 3,000 chemical barrels retrieved from major river of NE China

CHANGCHUN, July 30 (Xinhua) -- Local authorities said 2,978 barrels have been retrieved as of noon time Friday after they were swept by rain-triggered floods into the Songhua River in northeast China.

About 4,000 others were still to be recovered, said officials with Jilin Provincial Government. Full story

Special Report: China Fights Against Floods